• Archives of Pharmacal Research
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• v.15 no.2
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• pp.142-145
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• 1992

A novel preparative method for hexaprofen, which is a potent antiinflammatory agent, is described. Friedel-Crafts reaction of cyclohexylbenzene with ethyl $\alpha$-chloro-$\alpha$-(methylthio) acetate 1 and $\alpha$-chloro-$\alpha$-(methylthio) acetonitrile 2 afforded ethyl 2-(methylthio)-2-(4-cyclohexylphenyl) acetate 7 and 2-methylthio-2-(4-cyclohexylphenyl) acetonitrile 8, respectively. Compounds 7 and 8 were converted into the corresponding ethyl 2-methylthio-2-(4-cyclohexylphenyl) propionate 9 and 2-methylthio-2-(4-cyclohexylphenyl) propionitrile 10 by methylation with sodium hydride and methyl iodide. Hexaprofen 13 was prepard by hydrolysis of ethyl 2-(4-cyclohexylphenyl) propionate 11 and of 2-(4-cyclohexylphenyl) propionitrile 12 followed by desulfurization of compounds 9 and 10.

• YAKHAK HOEJI
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• v.33 no.4
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• pp.237-240
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• 1989

A new synthetic method for tiaprofenic acid, which is a potent anti-inflammatory agent, was described. Friedel-Crafts reaction of thiophene with ethyl ${\alpha}-chloro-{\alpha}-(methylthio)$ acetate (1) gave ethyl ${\alpha}-methylthio-2-thiopheneacetate$ (3). Ethyl ${\alpha}-methyl-2-thiopheneacetate$ (5) was prepared by treatment of (3) with NaH and MeI, followed by desulfurization with zinc dust-acetic acid of the resultant ethyl ${\alpha}-methyl-{\alpha}-methylthio-2-thiopheneacetate$ (4). Tiaprofenic acid (7) could be easily synthesized by benzoylation of (5) and hydrolysis of the resultant ethyl $5-benzoyl-{\alpha}-methyl-2-thiopheneacetate$ (6).

• YAKHAK HOEJI
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• v.36 no.2
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• pp.137-139
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• 1992

A new method for xenbucin, which is a antihypercholesteremic agent, is described. Friedel-Crafts reaction of biphenyl with ethyl ${\alpha}-chloro-{\alpha}-(methylthio)acetate(1)$ afforded ethyl 2-methylthio-2-(4-biphenylyl)acetate(2). Ethyl 2-(4-biphenylyl)butyrate(4) was obtained by ethylation of (2) with NaH and $C_2H_5I$, followed by desulfurization of the resultant ethyl 2-methylthio-2-(4-biphenylyl)butyrate(3) with zinc dust in acetic acid. Xenbucin was synthesized by hydrolysis of (4).

• YAKHAK HOEJI
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• v.36 no.4
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• pp.341-344
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• 1992

A facile method for tolmetin, which is a potent antiinflammatory agent, is described. Friedel-Crafts reaction of 1-methylpyrrole with ethyl ${\alpha}-chloro-{\alpha}-(methylthio)acetate$ (1) gave ethyl ${\alpha}-methylthio$-1-methyl-2-pyrroleacetate (4), which was readily converted into ethyl 1-methyl-2-pyrroleacetate (5) by reductive desulfurization with zinc dust in acetic acid. Tolmetin was synthesized by Friedel-Crafts acylation of (5) with p-toluoyl chloride, followed by hydrolysis of the resultant ethyl 5-(p-toluoyl)-1-methylpyrrole-2-acetate (6).

• YAKHAK HOEJI
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• v.36 no.2
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• pp.126-128
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• 1992

A new method for felbinac, which is a potent anti-inflammatory agent, is described. Friedel-Crafts reaction of biphenyl with ethyl ${\alpha}-chloro-{\alpha}-(methylthio)acetate(1)$ afforded ethyl 2-methylthio-2-(4-biphenylyl)acetate(4). Felbinac (7) was synthesized by desulfurization of compound (4) with zinc dust in acetic acid, followed by hydrolysis of the resultant ethyl 2-(4-biphenylyl)acetate (6).

• YAKHAK HOEJI
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• v.35 no.2
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• pp.119-122
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• 1991

A convenient method for the synthesis of ibuproxam, which is a non steroidal antiinflammatory agent, is reported. Friedel-Crafts reaction of isobutylbenzene with ethyl $\alpha$-chloro-$\alpha$-(methylthio)acetate (3) gives ethyl $\alpha$-methylthio-(p-isobutylpheny) acetate (4). Ethyl 2-methylthio-2-(4-isobutylphenyl) propionate (5) is obtained from methylation of the compound (4) with NaH and Mel. lbuproxam (7) is easily synthesized by reductive desulfurization of the compound (5) with zinc dust-acetic acid or Raney nickel, followed by treatment of the resultant ethyl 2-(4-isobutyl-pheny) propionate (6) with H$_{2}$NOH-HCI.

• YAKHAK HOEJI
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• v.35 no.2
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• pp.131-134
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• 1991

A new method for the synthesis of butibufen, which is a non steroidal anti-iriflammatory agent, is described. Friedel-Crafts reaction of isobutylbenzene with ethyl $\alpha$-chloro-.alpha.-(methylthio) acetate (1) gives ethyl $\alpha$-methylthio-(p-isobutylphenyl)acetate (2). Ethyl 2-methylthio-2-(4-isobutylphenyl)butyrate (3) is obtained from treatment of the compound (2) with NaH and Etl. Butibufen (5) is synthesized by reductive desulfurization of the compound (3) with zinc dust-acetic acid or Raney nickel, followed by hydrolysis of the resultant ethyl 2-(4-isobutylphenyl)butyrate (4).

• YAKHAK HOEJI
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• v.32 no.5
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• pp.340-342
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• 1988

New synthetic method for ibuprofen, which is a potent antiinflammatory agent, was described. Ethyl ${\alpha}-methylthio-p-isobutylphenylacetate$ was obtained from Friedel-Crafts reaction of isobutylbenzene with ethyl ${\alpha}-chloro-{\alpha}-(methylthio)acetate$ in the presence of $SnCl_4$. Ibuprofen was prepared in good yield by treatment of ethyl ${\alpha}-methylthio-p-isobutylphenylacetate$ with NaH and MeI, followed by desulfurization with zinc dust-acetic acid and hydrolysis of the resultant ethyl 2-methylthio-2-(4-isobutylphenyl)propionate.

• YAKHAK HOEJI
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• v.34 no.3
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• pp.212-214
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• 1990

A new synthetic method for bufexamac, which is a potent anti-inflammatory agent, was described. Friedel-Crafts reaction of butoxybenzene (2) with ethyl ${\alpha}-chloro-{\alpha}-(methylthio)acetate$ (1) gave ethyl 2-methylthio-2-(p-butoxyphenyl) acetate (3). Ethyl 2-(p-butoxyphenyl)acetate (4) was prepared by desulfurization of compound (3) with zinc dust-acetic acid. Bufexamac (5) could be easily synthesized by treatment of compound (4) with hydroxylamine HCl.

• YAKHAK HOEJI
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• v.35 no.5
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• pp.389-393
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• 1991

A convenient method for the synthesis of indobufen, which is a potent antiinflammatory agent, was described. Ethyl 2-phenylbutyrate(4) was prepared by Friedel-Crafts reaction of benzene with ethyl $\alpha$-chloro-$\alpha$-(methylthio)acetate(l) followed by ethylation and desulfurization of the resultant ethyl 2-(methylthio)phenylacetate(2). Ethyl 2-(p-aminophenyl)butyrate(6) was prepared by nitration of (4) and successive reduction of ethyl 2-(p-nitrophenyl) butyrate(5). Indobufen was obtained by condensation reaction of (6) with phthalic anhydride followed by reduction and hydrolysis of the resultant ethyl 2-[p-(1, 3-dioxo-2-isoindolinyl)phenyl]butyrate(7).